Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
CA 02912742 2015-11-23
WATER TANK FALL ARREST AND RESCUE APPARATUS
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of the filing date of United States
Provisional Patent Application Serial Number 62/084,044, filed 25 November
2014,
for "Water Tank Fall and Arrest System".
BACKGROUND
[0002] This disclosure relates to a transportable water tank having a fall
arrest
and rescue apparatus incorporated into the top of the water tank. In
particular, the
disclosure includes the use of a fall arrest cable tie-off assembly, a rescue
kit, and a
davit arm device that are all self-contained by the water tank for ease of
accessibility.
[0003] Keeping mobile equipment operational is a major concern for many
industries. For example, in the mining industry, the general construction
industry,
and the highway construction industry, the operational availability of this
equipment
is crucial to the success of the business. One piece of equipment often used
in
these industries is a water tanker. The water tanker is used to spray water
onto the
surface soil to control dust and prevent dust from drifting to surrounding
areas.
[0004] The safety of the personnel responsible for maximizing the
operational
availability of the water tanker is important. At times, personnel may access
the top
of a water tank, for example, to access various components, such as water
cannons,
spray valves and lights, or to conduct an inspection of the tank and its
components.
Some of these components may be close to the edge of the top of the tank. The
top
of a water tank mounted to a truck chassis may be 15 feet to 30 feet above
ground
level, depending on the size of the vehicle and the tank capacity. Falls from
these
heights could cause serious bodily injury or even death.
[0005] Another aspect of the inspection and maintenance activities that
must be
taken into consideration is how to rescue personnel should an emergency occur
while people are inside of, or on top of, the water tank. Rescue plans
describing how
to extract a person from the top or from the inside of a tank in the event of
an
emergency may exist, but these plans may neglect to identify a safe and
expeditious
means of getting an injured person from the top of the tank to the ground and
into
the care of advanced medical personnel.
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SUMMARY
[0006] The present disclosure provides a water tank safety system that
overcomes many of the shortcomings of prior designs. The present system
includes
various features. For example, personnel may attach the lanyard of their
safety
harness to a fall arrest tie-off assembly. The fall arrest tie-off assembly
allows
personnel to access all areas on top of the tank and is designed to prevent a
fall
beyond the length of the harness lanyard.
[0007] The safety system may also include a rescue kit secured to the top
of the
water tank for easy access by rescue personnel in an emergency. The rescue kit
contains various items required to conduct a proper rescue. These items are
used to
rescue a person from the interior of the tank and to lower the patient from
the top of
the tank to the ground. The items include, but are not limited to, a self-
braking
descender, steel carabiners, a rope grab, a short haul pulley, anchor straps,
and
rope. The items are typically stored in a water-proof storage bag.
[0008] The water tank safety system may include a rescue device comprised
of a
davit arm, a davit arm base and fall arrest tie-offs. The davit arm is stored
on top of
the tank near the rescue kit. The davit arm is inserted into a davit arm base
that is
mounted to a davit arm mount bracket. The mount bracket is permanently
attached
to the top of the water tank. The davit arm utilizes various components in the
rescue
kit and is used to lower a patient from the top of the water tank to the
ground.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Other features and advantages of the present disclosure will be
apparent
from reference to the following Detailed Description taken in conjunction with
the
accompanying Drawings, in which:
[0010] FIGURE 1 depicts a side elevation view of a water tank on a vehicle
chassis;
[0011] FIGURE 2 depicts a front isometric view of a water tank with the
safety
system installed thereon;
[0012] FIGURE 3 depicts an isometric view of a shuttle sliding over cable
and
system anchor components of the fall arrest assembly;
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[0013] FIGURE 4 depicts a cross-sectional view of the shuttle sliding over
the
cable and system anchor components of the fall arrest assembly;
[0014] FIGURES 5A, 5B, and 5C depict perspective views of elements of the
cable and anchor components of Figure 2; and
[0015] FIGURE 6 depicts a perspective view of a rescue device.
DETAILED DESCRIPTION
[0016] Figure 1 depicts a representative vehicle 10 for carrying a water
tank 12.
The configuration shown is typical of a water tanker truck used in the mining
industry
for dust suppression and fire control. However, the water tank 12 may be
attached
to other types of vehicles 10 such as on-highway vehicles, trailers, or the
like. Those
skilled in the art will appreciate that the tank 12 may be constructed with
various
physical dimensions to accommodate the various sized vehicles 10 on which the
tank 12 may be mounted.
[0017] Figure 2 depicts a representative water tank 12 on which a fall
arrest
assembly 20, a rescue device 30 and a rescue kit 40 are installed according to
the
present disclosure. The configuration shown is typical of a water tank 12 used
in the
mining industry for dust suppression and fire control. The water tank 12
includes a
top 14 on which the fall arrest assembly 20, rescue device 30 and rescue kit
40 are
attached, as well as a ladder 16 that provides access from the vehicle 10 deck
to the
top 14 of the water tank 12. In some embodiments, the top 14 of the water tank
12
may also be accessed from the vehicle 10 deck by other devices such as a
stairway.
Those skilled in the art will appreciate that the fall arrest assembly 20 and
rescue
device 30 of the present disclosure may be constructed with various physical
dimensions and configurations to accommodate the various sized water tanks 12,
or
other devices on which the fall arrest assembly 20, rescue device 30, and
rescue kit
40 may be installed.
[0018] Typically, the fall arrest assembly 20 is installed on the top 14 of
the water
tank 12 during manufacturing of the water tank 12. However, the fall arrest
assembly 20, the rescue device 30 and the rescue kit 40 need not be installed
during
the manufacture of the water tank 12 but may also be retro-fitted to an
existing water
tank 12. The fall arrest assembly 20 includes several anchors 22 mounted on
mounting blocks 23, a plurality of which are affixed around the top 14 of the
water
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tank 12. A safety cable 24 is routed through a loop or eyelet formed in the
top of
each of the anchors 22 and the cable 24 is put into tension, typically the
tension
suggested by the manufacturer, as will be understood by one of skill in the
art. The
fall arrest assembly 20 may fashioned from elements offered in the industry;
the
embodiment depicted relies heavily on the Skyline Horizontal Anchor Device
offered
by Skylotec GmbH of Neuwied, Germany.
[0019] Figure 5A depicts two anchors 22, one curving in one direction and
the
other in the opposite direction. This opposite curvature permits the cable 24
to be
curved around the top 14 of the water tank 12. As a result, the entire upper
surface
14 of the water tank 12 may be visited by a worker without removing the
worker's
lanyard 52 from the shuttle 26.
[0020] Figure 5B depicts a termination anchor 42 on a mounting block 23. In
the
embodiment depicted in Figure 5B, a compensator 44 affixed to the termination
anchor 42 includes an integrated eye bolt to which a first end of the cable 24
is
attached. The compensator 44 provides a certain degree of shock absorption to
compensate for tension in the cable 24. If the compensator 44 undergoes
tension
beyond a certain point (typically set by the manufacturer during manufacture
of the
compensator), the eye bolt over-extends, providing visual evidence to notify
users
that the cable 24 has been stretched too far, and the compensator 44 needs to
be
replaced.
[0021] Figure 50 depicts another termination anchor 42 on a mounting block
23.
In the embodiment depicted in Figure 5C, the second end of the cable 24 is
attached
to a wire rope thimble 52. The thimble 52 connects to a turnbuckle 54 which in
turn
connects to a tension indicator 56. The turnbuckle 54 may be used to increase
or
decrease the tension in the cable 24, as indicated by the tension indicator
56.
[0022] Prior to accessing the top 14 of the water tank 12, personnel put on
an
OSHA, ANSI, CSA, or other approved safety harness 50. A shuttle 26 (see
Figures
3 and 4) is attached to the safety cable 24 of the fall arrest assembly 20.
When
personnel access the top 14 of the water tank 12, the personnel attach a
lanyard 52
from the safety harness 50 to the shuttle 26. Personnel may then access the
entire
top 14 of the water tank 12 to perform inspection or maintenance tasks while
attached to the fall arrest assembly 20.
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[0023] In the embodiment depicted in Figure 2, personnel may also access an
entry point 60 into the water tank 12 while being attached to the fall arrest
assembly
20. Once at the entry point 60 on the top 14 of the water tank 12, personnel
may
detach the lanyard 52 from the shuttle 26 and access the interior of the water
tank 12
to perform inspection, maintenance and cleaning functions. All personnel must
follow approved entry procedures specific to the location prior to entering
the water
tank 12. The approved entry procedure will vary from site to site based on the
governing safety regulations. Although Figure 2 depicts an entry point 60 for
the
Westech Stairway Access Tank (this tank is the subject of U.S. Patent
Application
Serial No. 14/345,726 filed March 19, 2014, the disclosure of which is
incorporated
herein in its entirety by this reference), different embodiments of the water
tank 12
may have other entry point 60 configurations.
[0024] Figure 3 depicts one embodiment of a shuttle 26 and illustrates how the
shuttle 26, when attached to the cable 24 of the fall arrest assembly 20,
slides along
the cable 24 and the anchors 22. The cable 24 is routed through each of the
anchors 22 of the fall arrest assembly 20. The inside diameter of the shuttle
26 is
large enough so as to be able to slide over the anchors 22 through which the
cable
24 is routed. Typically, the shuttle 26 has a locking mechanism that secures
the
shuttle 26 around the cable 24 and prevents the shuttle 26 from accidentally
detaching from the cable 24.
[0025] Figure 4 is a cross-sectional view of one of the anchors 22 and the
shuttle
26 depicted in Figure 3. Figure 4 depicts how the cable 24 is routed through
the
anchors 22. Figure 4 also depicts the clearance between the shuttle 26 and
both the
cable 24 and the anchor 22 that allows the shuttle 26 to freely slide around
on the fall
arrest assembly 20. It will appreciated by those skilled in the art that the
shuttle 26
and anchors 22 may have different configurations in different embodiments, all
of
which would meet the functionality requirements of the fall arrest assembly
20.
[0026] During the manufacture of the water tank 12, a rescue device 30, as
depicted by the embodiment shown in Figure 2, may be installed on the top 14
of the
water tank 12. As depicted in perhaps more detail in Figure 6, the rescue
device 30
includes a davit arm mount bracket 32 permanently attached to the top 14 of
the
water tank 10. A davit arm base 33 mounts to the mount bracket 32. Fall arrest
tie-
offs 34 are also permanently attached to the top 14 of the water tank 12. A
davit arm
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36 is stored on top 14 of the water tank 12 for ease of access in the case of
an
emergency that would require a person to be lowered off the top 14 of the
water tank
12 to the ground. As depicted in Figure 2, the davit arm 36 is mounted on the
davit
arm base 33 when in use.
[0027] A rescue kit 40 may be stored on top 14 of the water tank 12 for ease
of
access in case of an emergency. The rescue kit 40 contains various pieces of
equipment necessary or useful to perform a rescue from the water tank 12. The
equipment includes, but is not limited to, a self-braking descender, steel
carabiners,
a rope grab, a short haul pulley, anchor straps, and rope. The required
equipment in
each rescue kit 40 may be determined by the rescue team personnel responsible
for
conducting rescue activities.
[0028] In the event of an emergency where an individual is injured in the
interior
of the water tank 12, rescue personnel will utilize the fall arrest assembly
20, the
rescue device 30 and the equipment in the rescue kit 40 to perform a rescue.
In a
typical rescue scenario, a four person rescue team would arrive at the scene,
assess
the situation and suit-up with the necessary personal protection equipment
("PPE").
The PPE would typically include, but not be limited to, a safety harness 50
with
lanyard 52, safety glasses, hard hat, gloves, safety boots and air respirators
as
required. Two members of the rescue team are typically designated as the entry
team and the other two members are typically designated as the exterior team.
[0029] In the embodiment depicted in Figure 2, the rescue team members
would
use the ladder 16 (or other alternative means, such as a staircase or a
hydraulic
man-lift) to access the top 14 of the water tank 12. The entry team members
would
gather required equipment out of the rescue kit 40 to conduct the rescue from
the
interior of the water tank 12. While the entry team performed the required
actions to
get the survivor to the top 14 of the water tank 12, the exterior team members
would
attach their lanyards 52 to the fall arrest tie-offs 34 to ensure their safety
during the
rescue process. The exterior team would place the davit arm 36 into the davit
arm
base 32. The davit arm 36 would then be rigged with the proper equipment, such
as
rope, carabiners and a self-braking descender from the rescue kit 40.
[0030] Once the entry team got the survivor to the top 14 of the water tank
12, the
entry team members would also attach their lanyards 52 to shuttles 26 on the
fall
arrest assembly 20 or the fall arrest tie-offs 34 to ensure their safety
during the
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rescue process. If the survivor was wearing a safety harness 50, then the
survivor's
safety harness 50 would be directly attached to the davit arm 36 of the rescue
device
30. The survivor would be raised off the top 12 of the water tank 12 and the
davit
arm 36 would be rotated out over the side of the water tank 12. Once clear of
the
side of the water tank 12, the survivor would be lowered to the ground and
into the
care of advanced medical personnel. It will be appreciated that other rescue
equipment, such as a rescue basket, could be used with the rescue device 30 to
lower the survivor from the top 14 of the water tank 12 to the ground
depending on
the situation.
[0031] Although particular embodiments of the present invention have been
described, those of skill in the art will appreciate that various
modifications and
changes may be made by those skilled in the art without departing from the
spirit and
scope of the invention. The present invention may be embodied in other
specific
forms without departing from its structures, methods, or other essential
characteristics as broadly described herein and claimed hereinafter. The
described
embodiments are to be considered in all respects only as illustrative, and not
restrictive.
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